I don't take practice swings. I just step up to my ball and hit it. There's nothing worse than playing with somebody who shoots in the upper 90s but takes three practice swings before every shot.
Other things that are awkward about golf:
—Gimmes. I don't take them. I like to putt everything out. But some people always take them, and let's just say we have different definitions of what a gimme is (some say gimmes are anything within a putters-length, others say a grip's length.) One guy I played with said he takes everything within a body's length (dude was about 6-foot-5, too.) At least he admitted that he was a total hack and just liked to drink.
—Cheaters. Whether it's on the course or on the score card, it still ticks me off. Keep in mind, if it's some random guy I don't know, this doesn't bother me. But if I'm playing with a friend who I've never played with before, and the scorecard dictates who buys drinks or who gets razzed for the next five hours, then yeah, I'm annoyed.